Spinning machines for yarn and roving, especially ring spinning machines or flyer spinning machines, generally include pressure arm assemblies at each spinning station acting to apply upper drafting or drawing rollers to the lower rollers so that the roving, thread, filament, band or yarn is clamped in the nip of the resulting roller pair. These pressure or pressing arm assemblies generally comprise a main arm against which are braced the springs which serve to apply pressure to the associated upper rollers, and comprise guides for the upper rollers. The pressure arm assemblies also can each have an operating lever arranged above the main arm and angularly movable to correspondingly displace the main arm. This operating lever serves to transfer the main arm between its pressure-exerting position and its lifted or inactive position in which it does not exert pressure. Each work location of the machine can be equipped with a signal light for signaling disruptions at such work location.
A ring spinning frame of this type is known to have been in use in the Federal Republic of Germany in which each spinning location has a signalling light. This light is arranged on a carrier which, in turn, is arranged above the spindle of the respective spinning location and between two adjacent pressure-exerting assemblies. The light is switched to an "on" state by automatic actuation of a switch when a problem arises, for example when the filament yarn or roving breaks.
When the disruption is corrected or remedied, the associated switch is turned "off" and the light is "out".
It is a significant disadvantage in the known apparatus that the visibility of the indicator light or lights is rather poor, especially from a distance. In addition, the manner in which the signal lights are secured to the respective components is relatively cumbersome and this can easily lead to problems in operating the apparatus.